Answers

Add 84/21 and 42/18

1^st number: 4 0/21, 2^nd number: 2 6/18

84/21 + 42/18 is 19/3.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 18 is 126
   
   Next, find the equivalent fraction of both fractional numbers with denominator 126
2. For the 1st fraction, since 21 × 6 = 126,
   84/21 = 84 × 6/21 × 6 = 504/126
3. Likewise, for the 2nd fraction, since 18 × 7 = 126,
   42/18 = 42 × 7/18 × 7 = 294/126
4. Add the two like fractions:
   504/126 + 294/126 = 504 + 294/126 = 798/126
5. 798/126 simplified gives 19/3
6. So, 84/21 + 42/18 = 19/3
   In mixed form: 61/3

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